This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 2 | 3 |
| 3 | 4 |
| 4 | 9 |
| 5 | 36 |
| 6 | 25 |
| 7 | 120 |
| 8 | 105 |
| 9 | 280 |
| 10 | 441 |
| 11 | 2520 |
| 12 | 385 |
| 13 | 277200 |
| 14 | 70785 |
| 15 | 56056 |
| 16 | 585585 |
| 17 | 5045040 |
| 18 | 1446445 |
| 19 | 183783600 |
| 20 | 8729721 |
| 21 | 40646320 |
| 22 | 1322685 |
| 23 | 4655851200 |
| 24 | 37182145 |
| 25 | 1070845776 |
| 26 | 900951975 |
| 27 | 5949143200 |
| 28 | 6453758025 |
| 29 | 80313433200 |
| 30 | 215656441 |